Arrangement for regulating the response of an internal combustion engine with a turbo charger

Abstract

In order to be able to modify in a simple manner the response of a supercharged internal combustion engine as a function of the engine load, an arrangement is proposed in which the driver may regulate the charge air pressure build-up by means of a manual setting control. The manual setting control is connected to an electronic control unit which, as a function of detected engine parameters, controls the supercharging pressure with respect to desired values stored in the control unit. As a function of the adjusted position of the setting control, a reduction of the charge air pressure which is dependent on the engine load is effected. In this way, the driver can choose which response the engine will have for partial load ranges, where it is possible either to have full charge air pressure at all throttle positions or a gradual increase of the charge air pressure on increasing throttle opening.

We claim: 
     
       1. Arrangement for regulating the charge air pressure in an internal combustion engine supercharged by means of a charge air unit, comprising: a regulating member for regulating the supercharging pressure of the charge air unit;   a plurality of sensors for sensing different engine parameters, including at least one engine-load sensor for sensing the load of the engine;   electrical control means for applying control signals to the regulating member to regulate the charge air pressure, the control means being coupled to the sensors for receiving input signals therefrom and having a memory unit containing stored values for the desired charge air pressure as a function of the input signals supplied by the sensors; and   manually adjustable means coupled to the control means for supplying a charge air pressure reduction signal thereto, the control means reducing the value for the desired charge air pressure so that the value for the desired charge air pressure is reduced in response to decreasing instantaneous engine load as sensed by the engine load sensor, the degree of reduction being given by the charge reduction signal from the manually adjustable means.   
     
     
       2. Arrangement according to claim 1, wherein the engine load sensor comprises a throttle position sensor. 
     
     
       3. Arrangement according to claim 1, wherein the engine load sensor comprises an accelerator pedal position sensor. 
     
     
       4. Arrangement according to claim 1, wherein the manually adjustable means permits a manual adjustment of the degree of charge reduction between at least two reduction levels. 
     
     
       5. Arrangement according to claim 4, wherein at one reduction level the degree of charge pressure reduction is essentially negligible. 
     
     
       6. Arrangement according to claim 4, wherein the manually adjustable means provides essentially steplessly adjustment to intermediate positions between said at least two positions. 
     
     
       7. Arrangement according to claim 6, wherein the manually adjustable means comprises a slide potentiometer. 
     
     
       8. Arrangement according to claim 6, wherein the manually adjustable means comprises a turn potentiometer. 
     
     
       9. Arrangement according to claim 6, wherein the charge reduction signal from the manually adjustable means is proportional to the position of the manually adjustable means and the degree of reduction is proportional to said charge reduction signal. 
     
     
       10. Arrangement according to claim 6, wherein the manually adjustable means is arranged on the instrument panel of a vehicle drive by the supercharged engine, and is accessible for manual adjustment by the driver.